The organization's strategy is simple: Keep people talking -- about mustaches, and the larger issue of men's health.

Research last year showed that participants have, on average, 2,400 Movember-related conversations a month, Garone said. About 30 are face to face.

Social media causes that message to amplify, he said. Users have taken to Facebook pages and Twitter accounts to document their individual, ongoing facial hair activism.

It isn't just one person asking another, "Why the mustache?" The answer spreads to 100 -- or 1,000.

"The conversations do lead to a greater understanding," Garone said.

Movember encourages both men and women (nicknamed "Mo Sistas") to participate throughout the month by registering through Movember.com.

The website has evolved an elaborate internal slang, including terms such as "Mo Mentor" and "Gala Parté," which is what participants call their end-of-the-month celebrations, and it has information on everything from grooming tips to health risks.

The rules are simple: Don't start with any facial hair and end with a lot.